Q: This vehicles rpm is running at 2500 at 70 mph. The 4x4 & ABS light is on. Is it safe to drive it down the interstate ?

Vehicles are designed to operate with all their systems functioning in certain ways. When warning lights such as "4X4" or "ABS" are lit, there is a fault, or multiple faults in those systems preventing them from operating as they were designed. When an ABS fault is set, your brakes may function normally but the "anti-lock" system may not. It is possible that on slippery surfaces or under hard braking, the wheels can lock up, causing a loss of control. for that reason alone, I could not say the vehicle is "safe to drive."

The 4X4 system does rely on input from the ABS system to determine if any wheel is spinning faster than another. When that happens, the ABS system can apply braking to an individual wheel to reduce spinning and send power to wheels with better traction. The 4X4 and ABS lights being on together, can be related to one component failure.

Have a certified technician look into why the abs light is on and determine if the 4X4 light is related.